xref: /openbmc/linux/drivers/clk/clk-versaclock5.c (revision e5c86679)
1 /*
2  * Driver for IDT Versaclock 5
3  *
4  * Copyright (C) 2017 Marek Vasut <marek.vasut@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 /*
18  * Possible optimizations:
19  * - Use spread spectrum
20  * - Use integer divider in FOD if applicable
21  */
22 
23 #include <linux/clk.h>
24 #include <linux/clk-provider.h>
25 #include <linux/delay.h>
26 #include <linux/i2c.h>
27 #include <linux/interrupt.h>
28 #include <linux/mod_devicetable.h>
29 #include <linux/module.h>
30 #include <linux/of.h>
31 #include <linux/of_platform.h>
32 #include <linux/rational.h>
33 #include <linux/regmap.h>
34 #include <linux/slab.h>
35 
36 /* VersaClock5 registers */
37 #define VC5_OTP_CONTROL				0x00
38 
39 /* Factory-reserved register block */
40 #define VC5_RSVD_DEVICE_ID			0x01
41 #define VC5_RSVD_ADC_GAIN_7_0			0x02
42 #define VC5_RSVD_ADC_GAIN_15_8			0x03
43 #define VC5_RSVD_ADC_OFFSET_7_0			0x04
44 #define VC5_RSVD_ADC_OFFSET_15_8		0x05
45 #define VC5_RSVD_TEMPY				0x06
46 #define VC5_RSVD_OFFSET_TBIN			0x07
47 #define VC5_RSVD_GAIN				0x08
48 #define VC5_RSVD_TEST_NP			0x09
49 #define VC5_RSVD_UNUSED				0x0a
50 #define VC5_RSVD_BANDGAP_TRIM_UP		0x0b
51 #define VC5_RSVD_BANDGAP_TRIM_DN		0x0c
52 #define VC5_RSVD_CLK_R_12_CLK_AMP_4		0x0d
53 #define VC5_RSVD_CLK_R_34_CLK_AMP_4		0x0e
54 #define VC5_RSVD_CLK_AMP_123			0x0f
55 
56 /* Configuration register block */
57 #define VC5_PRIM_SRC_SHDN			0x10
58 #define VC5_PRIM_SRC_SHDN_EN_XTAL		BIT(7)
59 #define VC5_PRIM_SRC_SHDN_EN_CLKIN		BIT(6)
60 #define VC5_PRIM_SRC_SHDN_SP			BIT(1)
61 #define VC5_PRIM_SRC_SHDN_EN_GBL_SHDN		BIT(0)
62 
63 #define VC5_VCO_BAND				0x11
64 #define VC5_XTAL_X1_LOAD_CAP			0x12
65 #define VC5_XTAL_X2_LOAD_CAP			0x13
66 #define VC5_REF_DIVIDER				0x15
67 #define VC5_REF_DIVIDER_SEL_PREDIV2		BIT(7)
68 #define VC5_REF_DIVIDER_REF_DIV(n)		((n) & 0x3f)
69 
70 #define VC5_VCO_CTRL_AND_PREDIV			0x16
71 #define VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV	BIT(7)
72 
73 #define VC5_FEEDBACK_INT_DIV			0x17
74 #define VC5_FEEDBACK_INT_DIV_BITS		0x18
75 #define VC5_FEEDBACK_FRAC_DIV(n)		(0x19 + (n))
76 #define VC5_RC_CONTROL0				0x1e
77 #define VC5_RC_CONTROL1				0x1f
78 /* Register 0x20 is factory reserved */
79 
80 /* Output divider control for divider 1,2,3,4 */
81 #define VC5_OUT_DIV_CONTROL(idx)	(0x21 + ((idx) * 0x10))
82 #define VC5_OUT_DIV_CONTROL_RESET	BIT(7)
83 #define VC5_OUT_DIV_CONTROL_SELB_NORM	BIT(3)
84 #define VC5_OUT_DIV_CONTROL_SEL_EXT	BIT(2)
85 #define VC5_OUT_DIV_CONTROL_INT_MODE	BIT(1)
86 #define VC5_OUT_DIV_CONTROL_EN_FOD	BIT(0)
87 
88 #define VC5_OUT_DIV_FRAC(idx, n)	(0x22 + ((idx) * 0x10) + (n))
89 #define VC5_OUT_DIV_FRAC4_OD_SCEE	BIT(1)
90 
91 #define VC5_OUT_DIV_STEP_SPREAD(idx, n)	(0x26 + ((idx) * 0x10) + (n))
92 #define VC5_OUT_DIV_SPREAD_MOD(idx, n)	(0x29 + ((idx) * 0x10) + (n))
93 #define VC5_OUT_DIV_SKEW_INT(idx, n)	(0x2b + ((idx) * 0x10) + (n))
94 #define VC5_OUT_DIV_INT(idx, n)		(0x2d + ((idx) * 0x10) + (n))
95 #define VC5_OUT_DIV_SKEW_FRAC(idx)	(0x2f + ((idx) * 0x10))
96 /* Registers 0x30, 0x40, 0x50 are factory reserved */
97 
98 /* Clock control register for clock 1,2 */
99 #define VC5_CLK_OUTPUT_CFG(idx, n)	(0x60 + ((idx) * 0x2) + (n))
100 #define VC5_CLK_OUTPUT_CFG1_EN_CLKBUF	BIT(0)
101 
102 #define VC5_CLK_OE_SHDN				0x68
103 #define VC5_CLK_OS_SHDN				0x69
104 
105 #define VC5_GLOBAL_REGISTER			0x76
106 #define VC5_GLOBAL_REGISTER_GLOBAL_RESET	BIT(5)
107 
108 /* PLL/VCO runs between 2.5 GHz and 3.0 GHz */
109 #define VC5_PLL_VCO_MIN				2500000000UL
110 #define VC5_PLL_VCO_MAX				3000000000UL
111 
112 /* VC5 Input mux settings */
113 #define VC5_MUX_IN_XIN		BIT(0)
114 #define VC5_MUX_IN_CLKIN	BIT(1)
115 
116 /* Supported IDT VC5 models. */
117 enum vc5_model {
118 	IDT_VC5_5P49V5923,
119 	IDT_VC5_5P49V5933,
120 };
121 
122 struct vc5_driver_data;
123 
124 struct vc5_hw_data {
125 	struct clk_hw		hw;
126 	struct vc5_driver_data	*vc5;
127 	u32			div_int;
128 	u32			div_frc;
129 	unsigned int		num;
130 };
131 
132 struct vc5_driver_data {
133 	struct i2c_client	*client;
134 	struct regmap		*regmap;
135 	enum vc5_model		model;
136 
137 	struct clk		*pin_xin;
138 	struct clk		*pin_clkin;
139 	unsigned char		clk_mux_ins;
140 	struct clk_hw		clk_mux;
141 	struct vc5_hw_data	clk_pll;
142 	struct vc5_hw_data	clk_fod[2];
143 	struct vc5_hw_data	clk_out[3];
144 };
145 
146 static const char * const vc5_mux_names[] = {
147 	"mux"
148 };
149 
150 static const char * const vc5_pll_names[] = {
151 	"pll"
152 };
153 
154 static const char * const vc5_fod_names[] = {
155 	"fod0", "fod1", "fod2", "fod3",
156 };
157 
158 static const char * const vc5_clk_out_names[] = {
159 	"out0_sel_i2cb", "out1", "out2", "out3", "out4",
160 };
161 
162 /*
163  * VersaClock5 i2c regmap
164  */
165 static bool vc5_regmap_is_writeable(struct device *dev, unsigned int reg)
166 {
167 	/* Factory reserved regs, make them read-only */
168 	if (reg <= 0xf)
169 		return false;
170 
171 	/* Factory reserved regs, make them read-only */
172 	if (reg == 0x14 || reg == 0x1c || reg == 0x1d)
173 		return false;
174 
175 	return true;
176 }
177 
178 static const struct regmap_config vc5_regmap_config = {
179 	.reg_bits = 8,
180 	.val_bits = 8,
181 	.cache_type = REGCACHE_RBTREE,
182 	.max_register = 0x76,
183 	.writeable_reg = vc5_regmap_is_writeable,
184 };
185 
186 /*
187  * VersaClock5 input multiplexer between XTAL and CLKIN divider
188  */
189 static unsigned char vc5_mux_get_parent(struct clk_hw *hw)
190 {
191 	struct vc5_driver_data *vc5 =
192 		container_of(hw, struct vc5_driver_data, clk_mux);
193 	const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;
194 	unsigned int src;
195 
196 	regmap_read(vc5->regmap, VC5_PRIM_SRC_SHDN, &src);
197 	src &= mask;
198 
199 	if (src == VC5_PRIM_SRC_SHDN_EN_XTAL)
200 		return 0;
201 
202 	if (src == VC5_PRIM_SRC_SHDN_EN_CLKIN)
203 		return 1;
204 
205 	dev_warn(&vc5->client->dev,
206 		 "Invalid clock input configuration (%02x)\n", src);
207 	return 0;
208 }
209 
210 static int vc5_mux_set_parent(struct clk_hw *hw, u8 index)
211 {
212 	struct vc5_driver_data *vc5 =
213 		container_of(hw, struct vc5_driver_data, clk_mux);
214 	const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;
215 	u8 src;
216 
217 	if ((index > 1) || !vc5->clk_mux_ins)
218 		return -EINVAL;
219 
220 	if (vc5->clk_mux_ins == (VC5_MUX_IN_CLKIN | VC5_MUX_IN_XIN)) {
221 		if (index == 0)
222 			src = VC5_PRIM_SRC_SHDN_EN_XTAL;
223 		if (index == 1)
224 			src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
225 	} else {
226 		if (index != 0)
227 			return -EINVAL;
228 
229 		if (vc5->clk_mux_ins == VC5_MUX_IN_XIN)
230 			src = VC5_PRIM_SRC_SHDN_EN_XTAL;
231 		if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN)
232 			src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
233 	}
234 
235 	return regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN, mask, src);
236 }
237 
238 static unsigned long vc5_mux_recalc_rate(struct clk_hw *hw,
239 					 unsigned long parent_rate)
240 {
241 	struct vc5_driver_data *vc5 =
242 		container_of(hw, struct vc5_driver_data, clk_mux);
243 	unsigned int prediv, div;
244 
245 	regmap_read(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV, &prediv);
246 
247 	/* The bypass_prediv is set, PLL fed from Ref_in directly. */
248 	if (prediv & VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV)
249 		return parent_rate;
250 
251 	regmap_read(vc5->regmap, VC5_REF_DIVIDER, &div);
252 
253 	/* The Sel_prediv2 is set, PLL fed from prediv2 (Ref_in / 2) */
254 	if (div & VC5_REF_DIVIDER_SEL_PREDIV2)
255 		return parent_rate / 2;
256 	else
257 		return parent_rate / VC5_REF_DIVIDER_REF_DIV(div);
258 }
259 
260 static long vc5_mux_round_rate(struct clk_hw *hw, unsigned long rate,
261 			       unsigned long *parent_rate)
262 {
263 	unsigned long idiv;
264 
265 	/* PLL cannot operate with input clock above 50 MHz. */
266 	if (rate > 50000000)
267 		return -EINVAL;
268 
269 	/* CLKIN within range of PLL input, feed directly to PLL. */
270 	if (*parent_rate <= 50000000)
271 		return *parent_rate;
272 
273 	idiv = DIV_ROUND_UP(*parent_rate, rate);
274 	if (idiv > 127)
275 		return -EINVAL;
276 
277 	return *parent_rate / idiv;
278 }
279 
280 static int vc5_mux_set_rate(struct clk_hw *hw, unsigned long rate,
281 			    unsigned long parent_rate)
282 {
283 	struct vc5_driver_data *vc5 =
284 		container_of(hw, struct vc5_driver_data, clk_mux);
285 	unsigned long idiv;
286 	u8 div;
287 
288 	/* CLKIN within range of PLL input, feed directly to PLL. */
289 	if (parent_rate <= 50000000) {
290 		regmap_update_bits(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV,
291 				   VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV,
292 				   VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV);
293 		regmap_update_bits(vc5->regmap, VC5_REF_DIVIDER, 0xff, 0x00);
294 		return 0;
295 	}
296 
297 	idiv = DIV_ROUND_UP(parent_rate, rate);
298 
299 	/* We have dedicated div-2 predivider. */
300 	if (idiv == 2)
301 		div = VC5_REF_DIVIDER_SEL_PREDIV2;
302 	else
303 		div = VC5_REF_DIVIDER_REF_DIV(idiv);
304 
305 	regmap_update_bits(vc5->regmap, VC5_REF_DIVIDER, 0xff, div);
306 	regmap_update_bits(vc5->regmap, VC5_VCO_CTRL_AND_PREDIV,
307 			   VC5_VCO_CTRL_AND_PREDIV_BYPASS_PREDIV, 0);
308 
309 	return 0;
310 }
311 
312 static const struct clk_ops vc5_mux_ops = {
313 	.set_parent	= vc5_mux_set_parent,
314 	.get_parent	= vc5_mux_get_parent,
315 	.recalc_rate	= vc5_mux_recalc_rate,
316 	.round_rate	= vc5_mux_round_rate,
317 	.set_rate	= vc5_mux_set_rate,
318 };
319 
320 /*
321  * VersaClock5 PLL/VCO
322  */
323 static unsigned long vc5_pll_recalc_rate(struct clk_hw *hw,
324 					 unsigned long parent_rate)
325 {
326 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
327 	struct vc5_driver_data *vc5 = hwdata->vc5;
328 	u32 div_int, div_frc;
329 	u8 fb[5];
330 
331 	regmap_bulk_read(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5);
332 
333 	div_int = (fb[0] << 4) | (fb[1] >> 4);
334 	div_frc = (fb[2] << 16) | (fb[3] << 8) | fb[4];
335 
336 	/* The PLL divider has 12 integer bits and 24 fractional bits */
337 	return (parent_rate * div_int) + ((parent_rate * div_frc) >> 24);
338 }
339 
340 static long vc5_pll_round_rate(struct clk_hw *hw, unsigned long rate,
341 			       unsigned long *parent_rate)
342 {
343 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
344 	u32 div_int;
345 	u64 div_frc;
346 
347 	if (rate < VC5_PLL_VCO_MIN)
348 		rate = VC5_PLL_VCO_MIN;
349 	if (rate > VC5_PLL_VCO_MAX)
350 		rate = VC5_PLL_VCO_MAX;
351 
352 	/* Determine integer part, which is 12 bit wide */
353 	div_int = rate / *parent_rate;
354 	if (div_int > 0xfff)
355 		rate = *parent_rate * 0xfff;
356 
357 	/* Determine best fractional part, which is 24 bit wide */
358 	div_frc = rate % *parent_rate;
359 	div_frc *= BIT(24) - 1;
360 	do_div(div_frc, *parent_rate);
361 
362 	hwdata->div_int = div_int;
363 	hwdata->div_frc = (u32)div_frc;
364 
365 	return (*parent_rate * div_int) + ((*parent_rate * div_frc) >> 24);
366 }
367 
368 static int vc5_pll_set_rate(struct clk_hw *hw, unsigned long rate,
369 			    unsigned long parent_rate)
370 {
371 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
372 	struct vc5_driver_data *vc5 = hwdata->vc5;
373 	u8 fb[5];
374 
375 	fb[0] = hwdata->div_int >> 4;
376 	fb[1] = hwdata->div_int << 4;
377 	fb[2] = hwdata->div_frc >> 16;
378 	fb[3] = hwdata->div_frc >> 8;
379 	fb[4] = hwdata->div_frc;
380 
381 	return regmap_bulk_write(vc5->regmap, VC5_FEEDBACK_INT_DIV, fb, 5);
382 }
383 
384 static const struct clk_ops vc5_pll_ops = {
385 	.recalc_rate	= vc5_pll_recalc_rate,
386 	.round_rate	= vc5_pll_round_rate,
387 	.set_rate	= vc5_pll_set_rate,
388 };
389 
390 static unsigned long vc5_fod_recalc_rate(struct clk_hw *hw,
391 					 unsigned long parent_rate)
392 {
393 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
394 	struct vc5_driver_data *vc5 = hwdata->vc5;
395 	/* VCO frequency is divided by two before entering FOD */
396 	u32 f_in = parent_rate / 2;
397 	u32 div_int, div_frc;
398 	u8 od_int[2];
399 	u8 od_frc[4];
400 
401 	regmap_bulk_read(vc5->regmap, VC5_OUT_DIV_INT(hwdata->num, 0),
402 			 od_int, 2);
403 	regmap_bulk_read(vc5->regmap, VC5_OUT_DIV_FRAC(hwdata->num, 0),
404 			 od_frc, 4);
405 
406 	div_int = (od_int[0] << 4) | (od_int[1] >> 4);
407 	div_frc = (od_frc[0] << 22) | (od_frc[1] << 14) |
408 		  (od_frc[2] << 6) | (od_frc[3] >> 2);
409 
410 	/* The PLL divider has 12 integer bits and 30 fractional bits */
411 	return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
412 }
413 
414 static long vc5_fod_round_rate(struct clk_hw *hw, unsigned long rate,
415 			       unsigned long *parent_rate)
416 {
417 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
418 	/* VCO frequency is divided by two before entering FOD */
419 	u32 f_in = *parent_rate / 2;
420 	u32 div_int;
421 	u64 div_frc;
422 
423 	/* Determine integer part, which is 12 bit wide */
424 	div_int = f_in / rate;
425 	/*
426 	 * WARNING: The clock chip does not output signal if the integer part
427 	 *          of the divider is 0xfff and fractional part is non-zero.
428 	 *          Clamp the divider at 0xffe to keep the code simple.
429 	 */
430 	if (div_int > 0xffe) {
431 		div_int = 0xffe;
432 		rate = f_in / div_int;
433 	}
434 
435 	/* Determine best fractional part, which is 30 bit wide */
436 	div_frc = f_in % rate;
437 	div_frc <<= 24;
438 	do_div(div_frc, rate);
439 
440 	hwdata->div_int = div_int;
441 	hwdata->div_frc = (u32)div_frc;
442 
443 	return div64_u64((u64)f_in << 24ULL, ((u64)div_int << 24ULL) + div_frc);
444 }
445 
446 static int vc5_fod_set_rate(struct clk_hw *hw, unsigned long rate,
447 			    unsigned long parent_rate)
448 {
449 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
450 	struct vc5_driver_data *vc5 = hwdata->vc5;
451 	u8 data[14] = {
452 		hwdata->div_frc >> 22, hwdata->div_frc >> 14,
453 		hwdata->div_frc >> 6, hwdata->div_frc << 2,
454 		0, 0, 0, 0, 0,
455 		0, 0,
456 		hwdata->div_int >> 4, hwdata->div_int << 4,
457 		0
458 	};
459 
460 	regmap_bulk_write(vc5->regmap, VC5_OUT_DIV_FRAC(hwdata->num, 0),
461 			  data, 14);
462 
463 	/*
464 	 * Toggle magic bit in undocumented register for unknown reason.
465 	 * This is what the IDT timing commander tool does and the chip
466 	 * datasheet somewhat implies this is needed, but the register
467 	 * and the bit is not documented.
468 	 */
469 	regmap_update_bits(vc5->regmap, VC5_GLOBAL_REGISTER,
470 			   VC5_GLOBAL_REGISTER_GLOBAL_RESET, 0);
471 	regmap_update_bits(vc5->regmap, VC5_GLOBAL_REGISTER,
472 			   VC5_GLOBAL_REGISTER_GLOBAL_RESET,
473 			   VC5_GLOBAL_REGISTER_GLOBAL_RESET);
474 	return 0;
475 }
476 
477 static const struct clk_ops vc5_fod_ops = {
478 	.recalc_rate	= vc5_fod_recalc_rate,
479 	.round_rate	= vc5_fod_round_rate,
480 	.set_rate	= vc5_fod_set_rate,
481 };
482 
483 static int vc5_clk_out_prepare(struct clk_hw *hw)
484 {
485 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
486 	struct vc5_driver_data *vc5 = hwdata->vc5;
487 
488 	/* Enable the clock buffer */
489 	regmap_update_bits(vc5->regmap, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
490 			   VC5_CLK_OUTPUT_CFG1_EN_CLKBUF,
491 			   VC5_CLK_OUTPUT_CFG1_EN_CLKBUF);
492 	return 0;
493 }
494 
495 static void vc5_clk_out_unprepare(struct clk_hw *hw)
496 {
497 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
498 	struct vc5_driver_data *vc5 = hwdata->vc5;
499 
500 	/* Enable the clock buffer */
501 	regmap_update_bits(vc5->regmap, VC5_CLK_OUTPUT_CFG(hwdata->num, 1),
502 			   VC5_CLK_OUTPUT_CFG1_EN_CLKBUF, 0);
503 }
504 
505 static unsigned char vc5_clk_out_get_parent(struct clk_hw *hw)
506 {
507 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
508 	struct vc5_driver_data *vc5 = hwdata->vc5;
509 	const u8 mask = VC5_OUT_DIV_CONTROL_SELB_NORM |
510 			VC5_OUT_DIV_CONTROL_SEL_EXT |
511 			VC5_OUT_DIV_CONTROL_EN_FOD;
512 	const u8 fodclkmask = VC5_OUT_DIV_CONTROL_SELB_NORM |
513 			      VC5_OUT_DIV_CONTROL_EN_FOD;
514 	const u8 extclk = VC5_OUT_DIV_CONTROL_SELB_NORM |
515 			  VC5_OUT_DIV_CONTROL_SEL_EXT;
516 	unsigned int src;
517 
518 	regmap_read(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num), &src);
519 	src &= mask;
520 
521 	if ((src & fodclkmask) == VC5_OUT_DIV_CONTROL_EN_FOD)
522 		return 0;
523 
524 	if (src == extclk)
525 		return 1;
526 
527 	dev_warn(&vc5->client->dev,
528 		 "Invalid clock output configuration (%02x)\n", src);
529 	return 0;
530 }
531 
532 static int vc5_clk_out_set_parent(struct clk_hw *hw, u8 index)
533 {
534 	struct vc5_hw_data *hwdata = container_of(hw, struct vc5_hw_data, hw);
535 	struct vc5_driver_data *vc5 = hwdata->vc5;
536 	const u8 mask = VC5_OUT_DIV_CONTROL_RESET |
537 			VC5_OUT_DIV_CONTROL_SELB_NORM |
538 			VC5_OUT_DIV_CONTROL_SEL_EXT |
539 			VC5_OUT_DIV_CONTROL_EN_FOD;
540 	const u8 extclk = VC5_OUT_DIV_CONTROL_SELB_NORM |
541 			  VC5_OUT_DIV_CONTROL_SEL_EXT;
542 	u8 src = VC5_OUT_DIV_CONTROL_RESET;
543 
544 	if (index == 0)
545 		src |= VC5_OUT_DIV_CONTROL_EN_FOD;
546 	else
547 		src |= extclk;
548 
549 	return regmap_update_bits(vc5->regmap, VC5_OUT_DIV_CONTROL(hwdata->num),
550 				  mask, src);
551 }
552 
553 static const struct clk_ops vc5_clk_out_ops = {
554 	.prepare	= vc5_clk_out_prepare,
555 	.unprepare	= vc5_clk_out_unprepare,
556 	.set_parent	= vc5_clk_out_set_parent,
557 	.get_parent	= vc5_clk_out_get_parent,
558 };
559 
560 static struct clk_hw *vc5_of_clk_get(struct of_phandle_args *clkspec,
561 				     void *data)
562 {
563 	struct vc5_driver_data *vc5 = data;
564 	unsigned int idx = clkspec->args[0];
565 
566 	if (idx > 2)
567 		return ERR_PTR(-EINVAL);
568 
569 	return &vc5->clk_out[idx].hw;
570 }
571 
572 static int vc5_map_index_to_output(const enum vc5_model model,
573 				   const unsigned int n)
574 {
575 	switch (model) {
576 	case IDT_VC5_5P49V5933:
577 		return (n == 0) ? 0 : 3;
578 	case IDT_VC5_5P49V5923:
579 	default:
580 		return n;
581 	}
582 }
583 
584 static const struct of_device_id clk_vc5_of_match[];
585 
586 static int vc5_probe(struct i2c_client *client,
587 		     const struct i2c_device_id *id)
588 {
589 	const struct of_device_id *of_id =
590 		of_match_device(clk_vc5_of_match, &client->dev);
591 	struct vc5_driver_data *vc5;
592 	struct clk_init_data init;
593 	const char *parent_names[2];
594 	unsigned int n, idx;
595 	int ret;
596 
597 	vc5 = devm_kzalloc(&client->dev, sizeof(*vc5), GFP_KERNEL);
598 	if (vc5 == NULL)
599 		return -ENOMEM;
600 
601 	i2c_set_clientdata(client, vc5);
602 	vc5->client = client;
603 	vc5->model = (enum vc5_model)of_id->data;
604 
605 	vc5->pin_xin = devm_clk_get(&client->dev, "xin");
606 	if (PTR_ERR(vc5->pin_xin) == -EPROBE_DEFER)
607 		return -EPROBE_DEFER;
608 
609 	vc5->pin_clkin = devm_clk_get(&client->dev, "clkin");
610 	if (PTR_ERR(vc5->pin_clkin) == -EPROBE_DEFER)
611 		return -EPROBE_DEFER;
612 
613 	vc5->regmap = devm_regmap_init_i2c(client, &vc5_regmap_config);
614 	if (IS_ERR(vc5->regmap)) {
615 		dev_err(&client->dev, "failed to allocate register map\n");
616 		return PTR_ERR(vc5->regmap);
617 	}
618 
619 	/* Register clock input mux */
620 	memset(&init, 0, sizeof(init));
621 
622 	if (!IS_ERR(vc5->pin_xin)) {
623 		vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
624 		parent_names[init.num_parents++] = __clk_get_name(vc5->pin_xin);
625 	} else if (vc5->model == IDT_VC5_5P49V5933) {
626 		/* IDT VC5 5P49V5933 has built-in oscilator. */
627 		vc5->pin_xin = clk_register_fixed_rate(&client->dev,
628 						       "internal-xtal", NULL,
629 						       0, 25000000);
630 		if (IS_ERR(vc5->pin_xin))
631 			return PTR_ERR(vc5->pin_xin);
632 		vc5->clk_mux_ins |= VC5_MUX_IN_XIN;
633 		parent_names[init.num_parents++] = __clk_get_name(vc5->pin_xin);
634 	}
635 
636 	if (!IS_ERR(vc5->pin_clkin)) {
637 		vc5->clk_mux_ins |= VC5_MUX_IN_CLKIN;
638 		parent_names[init.num_parents++] =
639 			__clk_get_name(vc5->pin_clkin);
640 	}
641 
642 	if (!init.num_parents) {
643 		dev_err(&client->dev, "no input clock specified!\n");
644 		return -EINVAL;
645 	}
646 
647 	init.name = vc5_mux_names[0];
648 	init.ops = &vc5_mux_ops;
649 	init.flags = 0;
650 	init.parent_names = parent_names;
651 	vc5->clk_mux.init = &init;
652 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_mux);
653 	if (ret) {
654 		dev_err(&client->dev, "unable to register %s\n", init.name);
655 		goto err_clk;
656 	}
657 
658 	/* Register PLL */
659 	memset(&init, 0, sizeof(init));
660 	init.name = vc5_pll_names[0];
661 	init.ops = &vc5_pll_ops;
662 	init.flags = CLK_SET_RATE_PARENT;
663 	init.parent_names = vc5_mux_names;
664 	init.num_parents = 1;
665 	vc5->clk_pll.num = 0;
666 	vc5->clk_pll.vc5 = vc5;
667 	vc5->clk_pll.hw.init = &init;
668 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_pll.hw);
669 	if (ret) {
670 		dev_err(&client->dev, "unable to register %s\n", init.name);
671 		goto err_clk;
672 	}
673 
674 	/* Register FODs */
675 	for (n = 0; n < 2; n++) {
676 		idx = vc5_map_index_to_output(vc5->model, n);
677 		memset(&init, 0, sizeof(init));
678 		init.name = vc5_fod_names[idx];
679 		init.ops = &vc5_fod_ops;
680 		init.flags = CLK_SET_RATE_PARENT;
681 		init.parent_names = vc5_pll_names;
682 		init.num_parents = 1;
683 		vc5->clk_fod[n].num = idx;
684 		vc5->clk_fod[n].vc5 = vc5;
685 		vc5->clk_fod[n].hw.init = &init;
686 		ret = devm_clk_hw_register(&client->dev, &vc5->clk_fod[n].hw);
687 		if (ret) {
688 			dev_err(&client->dev, "unable to register %s\n",
689 				init.name);
690 			goto err_clk;
691 		}
692 	}
693 
694 	/* Register MUX-connected OUT0_I2C_SELB output */
695 	memset(&init, 0, sizeof(init));
696 	init.name = vc5_clk_out_names[0];
697 	init.ops = &vc5_clk_out_ops;
698 	init.flags = CLK_SET_RATE_PARENT;
699 	init.parent_names = vc5_mux_names;
700 	init.num_parents = 1;
701 	vc5->clk_out[0].num = idx;
702 	vc5->clk_out[0].vc5 = vc5;
703 	vc5->clk_out[0].hw.init = &init;
704 	ret = devm_clk_hw_register(&client->dev, &vc5->clk_out[0].hw);
705 	if (ret) {
706 		dev_err(&client->dev, "unable to register %s\n",
707 			init.name);
708 		goto err_clk;
709 	}
710 
711 	/* Register FOD-connected OUTx outputs */
712 	for (n = 1; n < 3; n++) {
713 		idx = vc5_map_index_to_output(vc5->model, n - 1);
714 		parent_names[0] = vc5_fod_names[idx];
715 		if (n == 1)
716 			parent_names[1] = vc5_mux_names[0];
717 		else
718 			parent_names[1] = vc5_clk_out_names[n - 1];
719 
720 		memset(&init, 0, sizeof(init));
721 		init.name = vc5_clk_out_names[idx + 1];
722 		init.ops = &vc5_clk_out_ops;
723 		init.flags = CLK_SET_RATE_PARENT;
724 		init.parent_names = parent_names;
725 		init.num_parents = 2;
726 		vc5->clk_out[n].num = idx;
727 		vc5->clk_out[n].vc5 = vc5;
728 		vc5->clk_out[n].hw.init = &init;
729 		ret = devm_clk_hw_register(&client->dev,
730 					   &vc5->clk_out[n].hw);
731 		if (ret) {
732 			dev_err(&client->dev, "unable to register %s\n",
733 				init.name);
734 			goto err_clk;
735 		}
736 	}
737 
738 	ret = of_clk_add_hw_provider(client->dev.of_node, vc5_of_clk_get, vc5);
739 	if (ret) {
740 		dev_err(&client->dev, "unable to add clk provider\n");
741 		goto err_clk;
742 	}
743 
744 	return 0;
745 
746 err_clk:
747 	if (vc5->model == IDT_VC5_5P49V5933)
748 		clk_unregister_fixed_rate(vc5->pin_xin);
749 	return ret;
750 }
751 
752 static int vc5_remove(struct i2c_client *client)
753 {
754 	struct vc5_driver_data *vc5 = i2c_get_clientdata(client);
755 
756 	of_clk_del_provider(client->dev.of_node);
757 
758 	if (vc5->model == IDT_VC5_5P49V5933)
759 		clk_unregister_fixed_rate(vc5->pin_xin);
760 
761 	return 0;
762 }
763 
764 static const struct i2c_device_id vc5_id[] = {
765 	{ "5p49v5923", .driver_data = IDT_VC5_5P49V5923 },
766 	{ "5p49v5933", .driver_data = IDT_VC5_5P49V5933 },
767 	{ }
768 };
769 MODULE_DEVICE_TABLE(i2c, vc5_id);
770 
771 static const struct of_device_id clk_vc5_of_match[] = {
772 	{ .compatible = "idt,5p49v5923", .data = (void *)IDT_VC5_5P49V5923 },
773 	{ .compatible = "idt,5p49v5933", .data = (void *)IDT_VC5_5P49V5933 },
774 	{ },
775 };
776 MODULE_DEVICE_TABLE(of, clk_vc5_of_match);
777 
778 static struct i2c_driver vc5_driver = {
779 	.driver = {
780 		.name = "vc5",
781 		.of_match_table = clk_vc5_of_match,
782 	},
783 	.probe		= vc5_probe,
784 	.remove		= vc5_remove,
785 	.id_table	= vc5_id,
786 };
787 module_i2c_driver(vc5_driver);
788 
789 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
790 MODULE_DESCRIPTION("IDT VersaClock 5 driver");
791 MODULE_LICENSE("GPL");
792